The invention relates to the technical field of equipment for dispensing wiping materials such as paper or the like for wiping the hands or for use as toilet paper, the strip of material being in a folded or unfolded position.
The principle of this equipment was defined in the applicant's French patents FR 2332215 and 2340887, particularly as regards the device for controlling and moving the cutting blade into and then out of the drum in order to cut the strip of material pulled by the user.
To enable the field of the invention to be understood, it will be briefly mentioned that a piece of equipment of this type comprises a casing receiving a protective cover. The upper part of this casing receives supporting arms of a wiping material reel holder. In the lower part of the casing, a drum is fitted so that it can rotate freely between supporting flanges, and is designed to receive a cutting device comprising a blade and a blade holder inside the drum, which moves out of the drum for cutting. In the French patents cited above, a cam device is provided on one side of the drum and comprises a cam associated with the shaft of the drum and a cam follower associated with the axis of the blade holder, enabling the blade to move outwards when the drum rotates. A specific embodiment of the patent FR 2340887 also provides a cam slot formed on the flange of the drum receiving the cam follower.
To tackle the problem posed by the variations in quality and thickness of the reels of wiping material, and to improve the cutting, the applicant has developed a design of the device for controlling the outward movement of the blade described in PCT patent WO 00/40132. In this document, the device comprises, on one of the flanges and around a ring for the passage of the locking axis of the drum, a fixed profile forming a single unit with the body of the flange, constituting a guide path for a complementary part associated with the blade holder, the fixed profile and the complementary part having projecting profiles in the form of teeth to interact with each other when the drum rotates, creating an amplitude effect in relation to the movement of the part forming a lever when it swings, thus facilitating the cut. The shape of the complementary part is thus shown in FIGS. 1 and 2 to make its configuration clear. The cutting blade is therefore subjected to a movement out of the drum and then back into it, as a result of the position of the single-unit part associated with the blade holder with respect to the fixed profile forming the cam. In this embodiment, the blade holder requires the use of an elastic return spring.
The solution described in this PCT patent WO 00/40132 is entirely satisfactory when the diameter of the drum of the dispensing equipment is made to dispense material with a format of 13 inches. However, when smaller formats are required, of the order of 111 inches for example, difficulties have been encountered in pulling the strip of material, these difficulties being increased by the variable quality and thickness of the reels of material.
Since dispensing equipment with automatic cutting must have the best possible performance in view of its conditions of use, the applicant has sought a solution to further improve the operation of this type of equipment, in order to provide a high quality of operation for dispensing and cutting strips of wiping material in small formats, for example of the order of 11 inches or less.
As part of the same process and in the same context, the applicant wished to make the equipment even quieter by suppressing the clicking which occurs in particular when the cutting blade returns into the drum, as a result of the noise due to the stress of the return spring associated with the blade holder and incorporated in the drum.
These objects and others will be made clear by the remainder of the description.